Why is there a bottle opener in my board shorts?

Over the summer I bought a new pair of board shorts. I got them home, was about to try them on when I felt a heavy tag like thing in the side velcro pocket.

Oh No, I thought, they have left the store clip on which will spill ink all over my brand new swimmers before I have even had a chance to wear them.

Oh No, I couldn't have been further from the truth. The pair of board shorts that I had bought did not have an extra tag or anything like that, but actually had a small plastic metal type bottle opener in the side velcro pocket. What? That's right a bottle opener in the pocket. What is the marketing, or assumptions going on here. If you wear board shorts you drink beer. Or even worse, if you wear board shorts, for some reason you need kitchen utensils in your pants.

What about the type casting going on here? If a pair of board shorts includes a bottle opener, does a wetsuit now come with a swiss army knife? or even worse do budgie smugglers now have attached a cork screw?